import turtle
colors = ['red', 'green', 'blue']
def draw():
    turtle.pensize(10)
    for i in range(3):
        turtle.forward(60)
        turtle.dot(50, colors[i])
        turtle.backward(60)
        turtle.right(120)
def start():
    turtle.clear()
    draw()
    turtle.right(3)
    # 多少毫秒后定时执行某个函数
    turtle.ontimer(start, 300)
# 去除动画效果
turtle.tracer(False)
start()
turtle.done()
